I have a toy gun that fires spinning foam disks. It is pretty harmless of course. But it gave me an idea for the armory. Swords are fine for close up engagements, but a gun is hard to beat at a distance.

A graphene disk would be ideal for high-speed projection. The material of the disk would support high electric currents and therefore magnetic field interaction with the gun. Without bothering with too much detail, a future professional version of a disk gun could be made that fires ultra-thin (sharp) but highly strong graphene disks, spinning at high speed, and having minimal air resistance.

So the disks would shoot quite far, and self stabilising so fairly accurate, and very sharp, so would do damage. A high-speed cluster of them could be used to good effect to significantly damage or impede an enemy.

Electromagnetic forces could also be used to fire graphene darts. No new concepts are needed, the rail gun already exists and that mechanism would be perfect at any scale. Darts would scale too. Small darts with just a few layers of graphene would be very lightweight so convey limited mechanical damage, even if travelling fast, so they may be best suited for puncturing and short circuiting electrical equipment. Thicker and heavier ones would be much more lethal, adding mass and strength using any carbon material in the center, and being very streamlined and sharp if they taper the number of layers at the edges.

Cubic carbon is a fanciful material that may not even be possible to fabricate, using all 6 electrons to form bonds with neighbors in a cubic structure. It should be extremely hard, and such a material would be useful to make or add tips or edges to projectiles that could pierce or damage anything.

There is no shortage of traditional weapons, such as bows and arrows, swords, spears and an endless variety of guns, lasers etc. When none of these are permitted, you could fabricate and entire armory with nothing more than a roll of graphene tape.

Once graphene is easily producible, it will be possible to buy graphene tape. When I was a child, my friends and I used to make swords by rolling up tape measures and pushing the center through and drawing it out as far as possible to a point. If you roll up graphene tape and draw the center out, the point could be pretty sharp. Being graphene, it could also make a pretty strong rapier.

Also by winding some layers around a triangular cross section cardboard tube (or carbon fiber, or even a piece of scrap paper), a pretty rigid tube would result. Bending and tying the ends with strong graphene string or tape would result in a bow or sword.

Graphene weapons

The stringed bow would only need very fine string thanks to the huge strength of graphene. This would make a good bow but also make a cutting weapon in it own right. If a layer of tape instead of string were used, the same strength would be available with an even sharper edge.